Final Cut Pro Synchronize Clips not working: causes and fixes

In Final Cut Pro, Synchronize Clips fails in one of two ways. Either it is greyed out, or it runs and the clips stay out of sync. Apple's guide says that if no sync points can be found, the clips are synced at their respective starting points. So a synchronized clip can exist and still be wrong.

Below is a table of symptoms, causes and fixes. Then come the steps for one camera and for several. Facts about Final Cut Pro come from Apple's Final Cut Pro User Guide. Tips from Apple Community and Reddit are marked as common advice. The last part is for shoots with dozens of clips.

Symptoms, causes and fixes

The rows marked Apple's guide come from these pages of the Final Cut Pro User Guide: syncing audio and video, automatic audio sync, creating multicam clips and multicam editing tips. Common advice comes from Apple Community and r/finalcutpro.

Sync by sound in Final Cut Pro, step by step

One camera and a recorder. This is the most common case. Use Synchronize Clips.

1. In the browser, select the camera clip and the recorder file.
2. Choose Clip > Synchronize Clips, or press Option-Command-G.
3. Make sure Use audio for synchronization is selected. To mute the camera's own sound in the result, select Disable audio components on AV clips.
4. Click OK. A synchronized clip appears in the browser. Play it through before you cut.

Several cameras and a recorder. Use a multicam clip.

1. In the inspector, give every clip of one camera the same Camera Angle or Camera Name.
2. In the browser, select all camera clips and recorder files.
3. Choose File > New > Multicam Clip, or Control-click the selection and choose New Multicam Clip.
4. Click Use Custom Settings. Set Angle Assembly to Camera Angle or Camera Name, and keep Use audio for synchronization selected.
5. Click OK. If one angle is off, open the multicam clip in the angle editor and use Sync Angle to Monitoring Angle on it.

When the sound will not match. Mark the sync point by hand. Add a marker at the same moment in every clip, such as the clap. Apple's guide says Final Cut Pro looks for sync points such as markers you have added.

When there are dozens of clips

Everything above works on a selection you prepare. Each camera needs its angle, and each result a check. With a few clips that is quick. With dozens of files from several cameras and recorders, the preparation grows with every file.

With CamHeard there are no labels to set and no selection to build. It is an app for macOS and Windows that syncs cameras and recorders by sound. Final Cut Pro gets a ready project. The sync runs in CamHeard, so Final Cut Pro stays free while it works.

1. Copy the shoot as usual: one folder for the shoot, with a folder for each camera and each recorder inside.
2. Drag the shoot folder onto the CamHeard window and press Sync.
3. Choose Export, then Final Cut Pro, and save CamHeard_sync_FCP.fcpxml.
4. In Final Cut Pro, choose File > Import > XML… and pick that file. An event appears with a project of the same name, and the media links from your folders.

Better not to mix files from different cameras or recorders in one folder. With a folder per device, devices that were recording at the same time land on separate tracks.

One real shoot in CamHeard: 215 files, 8 cameras and a recorder, 8.9 hours of footage.

Clips that could not be synced arrive with the role Not Synced, so they do not pass for synced clips. You pick the colour for that role once, in the Timeline Index under Roles, and the library keeps it. No file is lost: unsynced clips go to the end of the timeline. Your files on disk are not changed.

Worth knowing. Final Cut Pro does not import Blackmagic RAW or old camcorder files such as .mpg and .mod, and one such file would break the whole import. So CamHeard leaves them out of the Final Cut Pro export. For BRAW angles, use the DaVinci Resolve export.

If the recorder has three or more channels, its tracks hear the first channel after the import, so assign the channels on the tracks by hand. The Matching timecode option does not apply to Final Cut Pro.

CamHeard 0.4.35 synced the shoot in the picture above in about a minute on a MacBook Pro with M3 Max. The more you shot, the longer it takes.

CamHeard runs on macOS 15 or later with Apple silicon, and on Windows 10 or 11, 64-bit. The first 14 days are the full app, with no card and no account. After that, projects up to 20 clips stay free. A licence costs $15 a month, $144 a year or $249 for life.

Frequently asked questions

How do I synchronize clips in Final Cut Pro?

Select the clips in the browser and choose Clip > Synchronize Clips, or press Option-Command-G. Keep Use audio for synchronization selected and click OK. For several cameras, choose File > New > Multicam Clip instead.

Why is Synchronize Clips greyed out in Final Cut Pro?

The common advice is to check where the clips are selected. Apple's steps start in the browser, so select the clips there, not in a project.

Why are my synchronized clips still out of sync?

Apple's guide says that if no sync points can be found, the clips are synced at their respective starting points. Check that both clips recorded the same moment with clear sound, or add a marker at the clap in each clip and sync again.

Why can't I edit while Final Cut Pro syncs?

Apple's guide warns that syncing by audio may result in long processing times during which Final Cut Pro is not available for editing. Syncing in smaller batches keeps each wait shorter.

Can CamHeard give Final Cut Pro a synced project?

Yes. Choose Export, then Final Cut Pro, and save the file. In Final Cut Pro, File > Import > XML… opens it as an event with a project of the same name. Clips that could not be synced arrive with the role Not Synced.